Nuclear engineer worried by lack of news from Japan

Pratt, Kan. —
The recent silence from Japan about conditions at the Fukushima Daiichi nuclear facility that was damaged in the March 11 earthquake and tsunami has a local man wondering just how severely the facility has been damaged.

The one thing he does know is that whatever is going on inside the reactors is very serious.

“It’s been kind of quiet out of Japan. This is not good,” said Eddie Petrowsky, nuclear engineer, area farmer and former employee of the Morris, Ill., Dresden No. 2 Nuclear reactor. “They’ve got some major problems.”
Petrowsky worked for two and half years as the lead nuclear engineer at the Morris facility, which is of the same type as the Fukushima facility, so he is familiar with its construction and operation.

When the earthquake and tsunami hit, Petrowsky watched with great interest how the facility would handle the crisis and control the threat of radiation contamination.

The Japanese are getting close to a point where they may have to turn each of the damaged reactors into a sand and concrete sarcophagus similar to the sarcophagus at the Chernobyl Nuclear Power Plant in Ukraine following an explosion on April 26, 1986, Petrowsky said.

The people working at the accident site have been exposed to a lot of radiation and Petrowsky said that survivability was probably slim and the workers would obviously have a lot of health issues.

When the earthquake and tsunami hit the reactors went into shutdown or scram. Water is supposed to be pumped continuously to keep the reactors cool but both the outside power and backup power failed. It was never assumed that the plant would lose coolant but when all the power failed that is exactly what happened.

Without those systems the critical coolant water that helps produce steam and keeps the reactor temperate at a safe level did not circulate and the reactors and the fuel pool began to heat up, Petrowsky said.

“They were worried about the water level,” Petrowsky said.

He wants to know why the Japanese didn’t bring in stand by generators. The country makes generators, American Navy vessels were in the area and had generators so why weren’t generators brought in, Petrowsky said.

The loss of water caused dangerous heat to build up leading to hydrogen gas explosions that damaged three of the plant’s six reactors.

Each of the nuclear reactors at the site has three containment vessels. The reactor is a containment vessel itself. Around the reactor is the primary containment vessel and around that is the secondary containment vessel, Petrowsky said.

When the water failed the temperature inside the reactor rose and caused pressure to buildup inside the primary containment vessel. To relieve that pressure, hydrogen steam was released from the primary containment vessel into the secondary containment vessel. The release caused a buildup of hydrogen the rejoined with oxygen and the pressure was too great and it blew the roofs off the secondary containment vessels. That is what people saw exploding on television.

So the primary containment vessels still held but inside the primary, without cooling water, damage continued and it is that damage plus the damage to the fuel pool that has Petrowsky wondering what the Japanese are going to do with the facility.

And it wasn’t just the water in the reactors that was the problem. When the boron fuel rods used to control the nuclear reaction in the reactor have been used up they are still radioactive and will stay that way for thousands of years.

Those rods are stored in a fuel pool that continuously covers the rods with recirculated water that keeps the temperature down and controls radiation. The fuel pool doesn’t have a containment building like the reactor but just a metal building.

When the water failed, the rods got hot and caused a hydrogen explosion that blew the top of the fuel pool building off releasing radioactive steam, Petrowsky said.

When the aircraft flew over the site and dropped boron on the facility they were trying to absorb the neutrons from the explosion. Boron rods absorb neutrons and are used to control the nuclear reaction. The more the rods are pushed into the reactor, the slower the reaction, the more they are pulled out, the greater the reaction.

The use of boron also told Petrowsky that the plant was using plutonium in the reactor. Most countries are prohibited from using plutonium because it is easy to use it to make nuclear weapons.

One thing that won’t happen at the plant is a reactor exploding like a nuclear bomb. A reactor would blow itself apart long before it could explode like a nuclear bomb.

“It’s virtually impossible for a reactor to blow up like a bomb,” Petrowsky said.